<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>Document</title>
</head>

<body>

    <script>
        let person = {
            getSay() {
                return "hello"
            }
        }

        // let tom = {
        //     getSay() {
        //         console.log(Object.getPrototypeOf(this))
        //         return Object.getPrototypeOf(this).getSay.call(this) + "jack"
        //     }

        // }
        // Object.setPrototypeOf(tom, person);
        // tom.getSay()


        // let tom = {
        //     getSay() {
        //         // 相当于Object.getPrototypeOf(this).getSay.call(this)
        //         return super.getSay() + ',jack';
        //     }
        // }


        // Object.setPrototypeOf(tom, person);
        // console.log(tom.getSay())


        // console.log(NaN == NaN)
        // console.log(Object.is(NaN, NaN))
    </script>
</body>

</html>